Resuscitation face mask

1. Technical Field

The present invention relates to masks for use in situations requiring the delivery of oxygen, and more specifically, for use on patients with various facial contours and sizes during the administration of anesthesia or resuscitative oxygen.

2. State of the Art

Ventilation masks are employed in numerous life-saving situations to facilitate oxygen delivery to the mouth or nose of the patient. Existing ventilation masks typically comprise of a large cover that fits over the nose and mouth of the patient and may include various features such as valves, tubes, rubber ridges, and balloons. These masks are particularly flexible and made of soft rubber, plastic, or the like.

Ventilation masks can be mouth-to-mouth resuscitation devices or manual and machine ventilation masks. Mouth-to-mouth devices are not often used in medical and surgical facilities. Ventilation or resuscitation masks are generally used for oxygen delivery to patients who do not have a breathing tube in place. These masks are different from plain oxygen masks which are merely used to deliver oxygen to a person who is capable of breathing on his/her own. Ventilation masks are specifically designed to be able to connect machines and devices that deliver oxygen to a person having severe difficulty in breathing or not breathing at all.

The principles of medicine always begin with the airway, breathing, and circulation. The key to cardiopulmonary resuscitation and anesthesiology is control of the airway, breathing, and circulation. Ventilation masks are used during emergencies when patients stop breathing or need assistance in breathing. Usually it is a bridging method to obtaining a secure airway such as an endotracheal breathing tube or laryngeal mask airway that is inserted into the throat.

Mask ventilation is the process of delivering oxygen to a person in need of assistance in breathing. This commonly occurs during respiratory failure. During cardiopulmonary resuscitation (CPR) and operative care, a respiratory therapist, anesthesiologist, or other health caregiver attempts to deliver oxygen to patients. Mask ventilation is important in maintaining oxygen supply to the body while the anesthesiology team prepares to place a breathing tube.

In surgery, there is a period where the patient is subject to anesthesia, and respiration is therefore maintained by an anesthetist. In order for an anesthetist to ventilate the patient properly for respiration, the mask used for oxygen delivery should provide an airtight seal between the mask and the patient\'s face.

It is, therefore, desirable that these ventilation masks can effectively seal around the face of the patient. Effective sealing requires masks to have the capability to accommodate various facial contours and sizes, facial deformity, or facial features such as beards, large noses, and sunken cheeks. Current masks often come in different sizes and possess some form of flexible seal to fit any variation of facial shapes and sizes. They are usually triangular in shape and fit over the patient\'s mouth and nose, and are generally pressed against the patient\'s face to cause an airtight seal. Consequently, patients complain of discomfort or pain from the pressure of the mask.

Existing mask designs fail to consider several important aspects including ergonomics, unusual facial size and shape of the patient, patient\'s comfort, the mask\'s connectablity to machines, proper anatomical physiological considerations, facilitation of proper mask ventilation, and detection of proper ventilation.

Ergonomics of masks for operators is still limited among masks available today. A comfortable fit can be very important in an operator\'s ability to use the mask. In some cases, mask ventilation may be needed for prolonged periods lasting several hours.

One common and obvious attempt to make masks fit a patient\'s face is to vary the shape of the mask\'s balloon and to make the balloon larger. This erroneous assumption that the balloon will prevent leaking is not always correct and can sometimes produce discomfort and be difficult for the operator to handle the mask. Furthermore, these masks are often not effective with elder or large patients.

Another common problem in current mask designs is the idea that a flat base and varied shape balloon are adequate. Designs where a common flat base sits above a flexible balloon do not provide balance and cannot effectively stabilize and seal the mask.

Connectablity of the masks to machines has been standardized so that the connector end of the mask fits a standard 22 mm plastic connector piece. Connection is usually done with the connector being perpendicular to the flat base which is not optimal.

The shape and size of a mask are important factors for fit. The mask must consider not only the anatomy of the patient\'s face but also the patient\'s comfort during ventilation. A mask that does not fit the patient properly may damage the patient\'s eyes, hinder the patient\'s sight, or cause discomfort.

Mask designs must also consider physiologic issues such as dead space. Dead space is the area in the mask where gas is trapped. An excessive dead space will allow mixing of exhaled air with fresh delivered oxygen air, thus, causing the patient to re-breathe carbon dioxide and hinder oxygenation.

The last two considerations, facilitation of proper mask ventilation and detection of proper ventilation, are generally not considered in previous mask designs. These two factors, proper mask technique and detection of gas exchange of oxygen for carbon dioxide in the lungs, are significant to the patient\'s health.

Ventilation masks are known in the art.

U.S. Pat. No. 3,695,264 entitled “Respiratory Mask,” issued on Oct. 3, 1972 and U.S. Pat. No. 5,429,683 entitled “Face Mask for Breathing,” issued on Jul. 4, 1995 disclose a flexible mask that allows some form of facial fit and sealing during oxygen delivery. However, these devices do not address the problems mentioned above.

None of the references cited above disclose the present invention.

It is the object of the present invention to provide effective mask sealing for all facial contours and sizes of the patients, particularly, for patients subject to anesthesia.

It is also the object of this invention to provide mask stability and comfort.